Interesting take. There are some serious issues with their analysis.
For starters they applied total CO2 emissions per kwh generated by China towards the calculation of CO2 used to build EV batteries. You can't do that because China has a diverse economy and all industries require different amounts of energy. For example, bitcoin farming is hugely energy intensive and there were, until recently, a bunch of them in China. In the defense of the authors they probably can't obtain more granular information out of China because the country has become so secretive so it's probably best that they never tried to make the comparison to begin with but then that would kill off half the article..
Secondly, Norwegians drive about 6.6k miles/yr whereas the US is around 13k miles/yr. The more miles you drive the more CO2/mile you save over the lifecycle of the vehicle.